The standard grape-harvesting machine has a portal-type chassis that rides along the row of vines, straddling these vines. Such a machine normally is provided with flexible clubs that strike the bases of the vines to shake the vines so that the grapes drop off into catchments provided in the machine. Such an arrangement is particularly effective since the ripe grapes can be readily dislodged from the vines in this manner, but the unripe ones cannot be shaken loose so readily.
The main disadvantage with such an apparatus is that the clubs damage the trunk of the vine, occasionally killing the vine or at least injuring it. Furthermore such an arrangement is not effective on tall vines, since the blow delivered to the base of the vine is attenuated greatly by the time it is transmitted to the upper portions of the vine. This last-mentioned disadvantage therefore results in incomplete harvesting and wastage of the grapes.